Premium
First Report of Rhizoctonia solani AG‐7 on Cotton in Egypt
Author(s) -
AbdElsalam Kamel A.,
Omar Moawad R.,
Aly Aly A.
Publication year - 2010
Publication title -
journal of phytopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.53
H-Index - 60
eISSN - 1439-0434
pISSN - 0931-1785
DOI - 10.1111/j.1439-0434.2009.01611.x
Subject(s) - rhizoctonia solani , biology , mycelium , rhizoctonia , agar , hypocotyl , horticulture , potato dextrose agar , agar plate , damping off , botany , pathogenicity , microbiology and biotechnology , seedling , bacteria , genetics
Eighty‐two isolates of Rhizoctonia solani were recorded from roots of naturally‐infected seedlings of the Egyptian cotton ( Gossypium barbadense L.). Anastomosis groups (AGs) of the isolates were determined by using 13 different AGs testers. Three (3.7%) of the isolates were identified as R. solani AG7, while the remaining isolates were belonging to the AG 2‐1, AG4 and AG5. The identification of the three isolates was based on the frequency of the C2 reaction with the AG7 tester isolate. No fusion was observed between AG7 and isolates representing the other 13 AGs. Colonies of AG7 isolates grown on potato dextrose agar (PDA), malt yeast agar (MYA) and melt peptone agar (MPA) were brown to dark brown with aerial mycelium and sclerotia. The isolates had pitted sclerotial clusters and brownish exudates after 21 days of culturing on PDA, but without clear zonation. Pathogenicity test under greenhouse conditions revealed that AG7 caused the common symptoms of damping–off, which included seed rot, lesions on the hypocotyls and root rot.